1. Technical Field
The present invention relates to a vehicle approach informing device configured to inform pedestrians and the like outside a vehicle that the vehicle is approaching.
2. Related Art
Conventional vehicle are primarily a gasoline-powered vehicle which runs using an engine as a drive source, and so a pedestrian can identify the presence of a vehicle by the engine sound generated by the vehicle when the vehicle is approaching from the rear or a blind spot of the pedestrian. However, no engine sound is generated by a vehicle such as an electric vehicle and a hybrid vehicle which run using an electric motor as a drive source, and it is difficult for a pedestrian to recognize whether the vehicle is approaching, by the sound of the vehicle.
Thus, vehicles equipped with an informing device have been proposed, the informing device being configured to output sound for informing people outside the vehicle such as pedestrians that the vehicle is approaching. For example, Japanese Unexamined Patent Application Publication No. 2009-40318 discloses a vehicle approach informing device configured to output simulated sound of tire noise from a speaker provided at the front end of a vehicle when the vehicle is running at a speed lower than or equal to a predetermined vehicle speed, the simulated sound having the same tone as that of the actual tire noise.
However, the sound for informing vehicle approach may be an annoying noise to the driver and the surroundings. For example, output of informing sound in a garage may be an annoying noise to the driver because the sound reverberates through the garage. For another example, a driver frequently drives the vehicle at a low speed in an area near the residence thereof, thus the sound for informing vehicle approach is constantly emitted, thereby causing an annoying noise to the neighbors.
In order to prevent the informing sound from being an annoying noise, an approach may be taken that allows a driver to disable the output of the informing sound at the driver's will. With this approach, the output of the informing sound is disabled at a place where the driver thinks that informing sound may cause an annoying noise, and thus the informing sound can be prevented from being an annoying noise. However, because informing sound is outputted to the outside of the vehicle, the driver inside the vehicle may continue to drive without being aware that the output of the informing sound has been stopped. In such a case, while the driver is not aware that the output of the informing sound has been stopped, a pedestrian may not be aware that the vehicle is approaching.